Summary

Latent autoimmune diabetes in adults (LADA) is a relatively new type of diabetes with a clinical phenotype of type 2 diabetes (T2D) and an immunological milieu characterized by high titers of islet autoantibodies, resembling the immunological profile of type 1 diabetes (T1D). Herein, we report a case of a young male, diagnosed with LADA based on both clinical presentation and positive anti-glutamic acid decarboxylase antibodies (GAD-abs), which were normalized after combined treatment with a dipeptidyl peptidase-4 inhibitor (DPP-4) (sitagliptin) and cholecalciferol.

Learning points

Anti-glutamic acid decarboxylase antibodies (GAD-abs) titers in young patients being previously diagnosed as type 2 diabetes (T2D) may help establish the diagnosis of latent autoimmune diabetes in adults (LADA).

Summary

We report the case of a 19-year-old boy, presenting several congenital malformations (facial dysmorphisms, cardiac and musculoskeletal abnormalities), mental retardation, recurrent respiratory infections during growth and delayed puberty. Although previously hospitalised in other medical centres, only psychological support had been recommended for this patient. In our department, genetic, biochemical/hormonal and ultrasound examinations were undertaken. The karyotype was 49,XXXXY, a rare aneuploidy with an incidence of 1/85 000–100 000, characterised by the presence of three extra X chromosomes in phenotypically male subjects. The hormonal/biochemical profile showed hypergonadotropic hypogonadism, insulin resistance and vitamin D deficiency. The patient was then treated with testosterone replacement therapy. After 12 months of treatment, we observed the normalisation of testosterone levels. There was also an increase in pubic hair growth, testicular volume and penis size, weight loss, homeostatic model assessment index reduction and the normalisation of vitamin D values. Moreover, the patient showed greater interaction with the social environment and context.

Learning points

In cases of plurimalformative syndrome, cognitive impairment, recurrent infections during growth and, primarily, delayed puberty, it is necessary to ascertain as soon as possible whether the patient is suffering from hypogonadism or metabolic disorders due to genetic causes. In our case, the diagnosis of hypogonadism, and then of 49,XXXXY syndrome, was unfortunately made only at the age of 19 years.

The testosterone replacement treatment, even though delayed, induced positive effects on: i) development of the reproductive system, ii) regulation of the metabolic profile and iii) interaction with the social environment and context.

However, earlier and timely hormonal replacement treatment could probably have improved the quality of life of this subject and his family.

S Solomou, R Khan, D Propper, D Berney and M Druce

Summary

A 33-year-old male was diagnosed with a metastatic neuroendocrine carcinoma of uncertain primary. He defaulted from follow-up without therapy and some months later developed episodic severe hypoglycaemia, which was found to be associated with inappropriately elevated insulin and C-peptide levels. It was considered likely that the neuroendocrine tumour was the source of the insulin secretion. Diazoxide and somatostatin analogue were used to control hypoglycaemia. Much later in the course of the disease, he developed metabolic derangement, increased skin pigmentation and psychological disturbance, without frankly Cushingoid physical findings. Investigations revealed highly elevated cortisol levels (the levels having previously been normal) with markedly raised ACTH levels, consistent with the co-secretion of ACTH and insulin by the tumour. Treatment with metyrapone improved his psychological state and electrolyte imbalance. Unfortunately, despite several cycles of first-, second- and third-line chemotherapy from the start of the first hormonal presentation onwards, imaging revealed widespread progressive metastatic disease and the patient eventually passed away. This case highlights the importance of keeping in mind the biochemical heterogeneity of endocrine tumours during their treatment.

Learning points

The clinical presentation of insulin-secreting tumours includes symptoms of neuroglycopaenia and sympathetic overstimulation.

Tumour-associated hypoglycaemia can be due to pancreatic insulinomas, and although ectopic hormone production occurs in a number of tumours, ectopic secretion of insulin is rare.

A possible switch in the type of hormone produced can occur during the growth and progression of neuroendocrine tumours and, when treating neuroendocrine tumours, it is important to keep in mind their biochemical heterogeneity.

Summary

Isolated GH deficiency type IA (IGHDIA) is an infrequent cause of severe congenital GHD, often managed by pediatric endocrinologists, and hence few cases in adulthood have been reported. Herein, we describe the clinical status of a 56-year-old male with IGHDIA due to a 6.7 kb deletion in GH1 gene that encodes GH, located on chromosome 17. We also describe phenotypic and biochemical parameters, as well as characterization of anti-GH antibodies after a new attempt made to treat with GH. The height of the adult patient was 123 cm. He presented with type 2 diabetes mellitus, dyslipidemia, osteoporosis, and low physical and psychological performance, compatible with GHD symptomatology. Anti-GH antibodies in high titers and with binding activity (>101 IU/ml) were found 50 years after exposure to exogenous GH, and their levels increased significantly (>200 U/ml) after a 3-month course of 0.2 mg/day recombinant human GH (rhGH) treatment. Higher doses of rhGH (1 mg daily) did not overcome the blockade, and no change in undetectable IGF1 levels was observed (<25 ng/ml). IGHDIA patients need lifelong medical surveillance, focusing mainly on metabolic disturbances, bone status, cardiovascular disease, and psychological support. Multifactorial conventional therapy focusing on each issue is recommended, as anti-GH antibodies may inactivate specific treatment with exogenous GH. After consideration of potential adverse effects, rhIGF1 treatment, even theoretically indicated, has not been considered in our patient yet.

Learning points

Severe isolated GHD may be caused by mutations in GH1 gene, mainly a 6.7 kb deletion.

Appearance of neutralizing anti-GH antibodies upon recombinant GH treatment is a characteristic feature of IGHDIA.

Recombinant human IGF1 treatment has been tested in children with IGHDIA with variable results in height and secondary adverse effects, but any occurrence in adult patients has not been reported yet.

Metabolic disturbances (diabetes and hyperlipidemia) and osteoporosis should be monitored and properly treated to minimize cardiovascular disease and fracture risk.

Cerebral magnetic resonance imaging should be repeated in adulthood to detect morphological abnormalities that may have developed with time, as well as pituitary hormones periodically assessed.